I'm sure there's linkage adjustment, generally if you can get into the gears eventually, means you need to adjust something. I would get the bentley manual and whatever resources you can for you car to do it correctly. A little common sense checking things out might help too. I don't know off the top of my head what the adjustment is, but if I was in your position I would hit up the previous suggestions.

Have you replaced the linkage bushings? That could be the problem, hope that's helpful